3.1.3 Confirmation of antibody reactivity 3.1.3.1 Patient's leukemic blasts (peripheral blood or marrow) must be documented to bind mAb 216 in vitro (Teng lab) 3.1.3.2 Patient's RBC documented to NOT express fetal "i" antigen and RBC shown to NOT bind mAb 216 in vitro (Teng lab)